The present invention relates to an adhesive article, specifically an adhesive article suitable for the protection of finished exterior surfaces of an automobile from damage or discoloration.
Automobiles require protection from the elements such as sun, airborne debris, dust, rainwater or other harmful matters that can damage, dull or discolor the paint on an automobile. Protection is required during transportation of automobiles from one location to another (e.g. from the manufacturing plant to the dealer) on trucks or ships.
Various surface protective sheets comprising a support and an adhesive layer formed on the support are known. Generally, a protective sheet consists of a low-cost, ultra-violet stabilized, impact resistant polyolefin sheet coated with a thin layer of adhesive. Examples of protective sheets can be found in, for example, U.S. Pat. No. 6,030,702 assigned to Nitto Denki Corporation (Osaka, JP) and Kansai Paint Co., Ltd. (Hyogo, JP). The automobile has a clearcoat finish on the paint that may not be fully cured prior to the application of the protective film. Despite the protective benefits of known flat protective films, these films may interfere with the incompletely cured clearcoat finish, causing defects in the painted system, for example surface defects in the clearcoat finish on the automobile paint. Additionally, the films may leave behind adhesive residue upon removal.
One common surface defect is the deterioration or discoloration of the paint system resulting from water or water vapor that is entrapped between the protective sheet and the paint system. The water or water vapor may be present between the protective sheet and the paint system for a sufficiently long period of time to cause damage. Such damage may occur even if the water and water vapor cannot be seen when applying the protective film.
Additionally, because protective films are applied in large sheets, it is difficult to apply the film without wrinkles and bubbles in the film, which can lead to extra moisture entrapment.
The present invention is directed to micro-channeled protective films that address the problems associated with known flat protective films.
The present invention relates to a film comprising a backing and an adhesive. The backing comprises a base layer comprising a first major surface and a second major surface, and at least two rails, each rail comprising a tip surface. The rails extend from the second major surface of the base layer and define micro-channels therebetween. The micro-channels comprise a channel surface. The film comprises an adhesive on the tip surface of the rails. At least a portion of the channel surface is substantially free of adhesive.
In other aspects of the invention the backing is multilayer. In certain embodiments, the base layer is multilayer, or the rails are multilayer, or both. In some embodiments, the base layer comprises a first material and the rails comprise a second material, the first material being different from the second material.
In some aspects of the present invention, the second major surface of the base layer is substantially free of adhesive. In other aspects of the invention, the rails have a side surface, and the side surface is substantially free of adhesive.
The present invention also relates to a method of protecting an automobile comprising preparing an automobile surface for application of a protective tape and applying a protective tape to the automobile surface. The protective tape comprises a backing and an adhesive. The backing comprising a base layer comprising a first major surface and a second major surface, and at least two rails having a tip surface, the rails extending from the second major surface of the base layer, the rails defining micro-channels therebetween, the micro-channels comprising a channel surface. The film comprises an adhesive on the tip surface of the rails.
In certain aspects of the invention, the method further comprises exposing the protective tape to an elevated temperature after applying the protective tape to the automobile surface to soften the rails and cause them to flow together to thereby partially or completely eliminate the micro-channels.
The present invention is additionally related to a method of manufacturing a protective film comprising providing at least one film forming material, providing an adhesive material, feeding the film forming material and the adhesive material into an extrusion process having a die, wherein the die has a profile, and simultaneously extruding the adhesive material and the film forming material through the die to create micro-channels in the film forming material.